Herbicidal 2-(2-imidazolin-2-yl)-benzazoles

Abstract

There are provided o-carboxy-(5-oxo-2-imidazolin-2-yl)benzoheterocyclic compounds wherein the fused heterocyclic ring system is a 5-membered ring containing one, two or three nitrogen atoms, derivatives of said benzoheterocyclic compounds and a method for the use therewith to control monocotyledenous and dicotyledenous plant species.

What is claimed is: 
     
       1. A compound having the structure ##STR79## wherein R 1  is hydrogen, di(C 1  -C 4 )alkylimino; C 1  -C 12  alkyl optionally substituted with one or more of the following: C 1  -C 4  alkoxy, C 1  -C 4  alkylthio, halogen, hydroxy, C 3  -C 6  cycloalkyl, benzyloxy, furyl, phenyl, halophenyl, C 1  -C 4  alkylphenyl, C 1  -C 4  alkoxyphenyl, nitrophenyl, carboxy, C 1  -C 4  alkoxycarbonyl, cyano or tri(C 1  -C 4 )alkylammonium halide;   C 3  -C 12  alkenyl optionally substituted with one or more of the following groups: C 1  -C 4  alkoxy, phenyl, halogen or C 1  -C 4  alkoxycarbonyl,   C 3  -C 6  cycloalkyl optionally substituted with one or more C 1  -C 4  alkyl groups,   C 3  -C 16  alkynyl optionally substituted with one or more C 1  -C 4  alkyl groups; or a cation;   R 2  is C 1  -C 4  alkyl;   R 3  is C 1  -C 4  alkyl or C 3  -C 6  cycloalkyl; and when R 2  and R 3  are taken together with the carbon to which they are attached they may represent C 3  -C 6  cycloalkyl optionally substituted with methyl;   B is hydrogen, COR 4  or SO 2  R 5  with the proviso that when B is COR 4  or SO 2  R 5 , R 1  is other than hydrogen or a cation and R 9  is other than hydrogen;   R 4  is C 1  -C 11  alkyl, chloromethyl or phenyl optionally substituted with halogen, nitro or C 1  -C 4  alkyl;   R 5  is C 1  -C 4  alkyl or phenyl optionally substituted with C 1  -C 4  alkyl;   X, Y and Z are each independently, N, or NR 9  ;   the ---------- configuration represents either a single bond or a double bond with the proviso that when any of X, Y or Z is NR 9 , then the ---------- configuration represents a single bond and with the further proviso that at least one of the ---------- configurations represents a single bond;   R 9  is hydrogen or C 1  -C 4  alkyl optionally substituted with one hydroxy or one to three halogens, C 1  -C 4  alkoxy groups or C 1  -C 4  alkylthio groups;   Q is hydrogen, halogen, C 1  -C 4  alkoxy or C 1  -C 4  alkyl optionally substituted with one to three of the following: halogen, C 1  -C 4  alkoxy, C 1  -C 4  alkylthio, or C 2  -C 4  alkenyl;   the optical isomers thereof when R 2  and R 3  are not the same;   the tautomers and geometric isomers thereof and the agriculturally acceptable acid addition salts thereof except when R 1  is a salt-forming cation.   
     
     
       2. The compound according to claim 1 wherein R 1  is hydrogen or a cation; R 2  is methyl; R 3  is isopropyl and B and Q are hydrogen. 
     
     
       3. The compound according to claim 2 wherein the compound has the structure, c or e. 
     
     
       4. The compound according to claim 3 wherein R 1  is hydrogen, C 1  -C 4  alkyl optionally substituted with halogen, C 1  -C 3  alkoxy, hydroxy, furyl, phenyl or halophenyl, C 3  -C 6  alkenyl, C 3  -C 6  alkenyl, C 3  -C 6  cycloalkyl, C 3  -C 6  alkynyl or a cation; R 2  is methyl; R 3  is isopropyl and B and Q are hydrogen. 
     
     
       5. The compound according to claim 1 wherein X is NR 9  and Y and Z are N. 
     
     
       6. The compound according to claim 5 wherein said compound has the structure, c, or e. 
     
     
       7. The method for the control of monocotyledonous and dicotyledonous plant species which comprises applying to the foliage of said plant species or to the soil or water containing seeds or other propagating organs of said plant species a herbicidally effective amount of a compound having the structure as described in claim 1. 
     
     
       8. The method according to claim 7 wherein X is NR 9  and Y and Z are N. 
     
     
       9. The method according to claim 7 wherein the compound is applied to the foliage of said plant species or to the soil or water containing seeds or other propagating organs of said plant species at a rate of about 0.016 kg/ha to 4.0 kg/ha. 
     
     
       10. A herbicidal composition which comprises an inert solid or liquid diluent and a herbicidally effective amount of a compound having the structure as described in claim 1. 
     
     
       11. The herbicidal composition according to claim 10 wherein the compound has the structure as described in claim 5.